Control for fluid power plants



Sept. 8, 1936./ H. H. FITCH 2,053,330

CONTROL FOR FLUID POWER PLANTS Filed April i7, 193s l TLB 50 50 'v l H5 A l [5l /434/ 7 r [33d unuuEM-:lununn NS INVENTOR. #afs/v51. F/TCH.

l a 45 wm ATTORNEYS.

1 other modification.

Patented Sept. 8, 1936 UNITED STATES CONTROL FOR FLUID POWER PLANTS Hurshel H. Fitch, Auburn, Ind., assignor to Auburn Foundry Inc., Auburn, Ind., a, corporation Application April 17,

16 Claims.

This invention relates to a combination valve arrangement.

This application is a continuation in part of application Serial No. 382,442, filed July 31, 1929 entitled Speed control units.

This invention is particularly directed to the specific valve arrangementwhich is embodied in a liquid pressure system including a source of pressure such as a pump, a device operable by said pressure and connected to the source thereof, a reservoir or the like from which the pump secures the liquid fordevice operation, and to which the device discharges.

All of the aforesaid is disclosed in the copending application previously referred to and is made a part of this disclosure.

The present invention, in common a part of the disclosure in the before mentioned application, is directed to certain mechanism that is interposed between the discharge from the device to the reservoir and which is associated with a by-pass construction automatically operable by the back pressure created by a throttle valve in the discharge from the device to the reservoir, and when desired, a relief valve controlled by-pass is incorporated for relieving excess pressure from the pump or source 0f pressure supply and to the reservoir and arranged to by-pass the device.

One feature of the present disclosure consists in the unitary arrangement of all of the parts into a compact unit.

The full nature of the invention will be understood from the accompanying drawing and the following description and claims.

In the drawing, Fig. 1 is a central sectional view through one forrnof the invention shown as a unitary arrangement, certain of the parts being shown in elevation. Y

Fig. 2 is a sectional view taken on line 2-2 of Fig. 1 and in the direction of the arrows.

Fig. 3 is a section through the pressure operlated valve controlling the control by-pass of an- Fig. 4 is a section taken on line 4--4 of Fig. 3.

Fig. 5 is a view partly in section of the throttling valve of the last mentioned modification.

Fig. 6 is a section taken on line 6-6 of Fig. 5.

In the present description Figs. 3 to 6 are identical with Figs. 4 to 7, inclusive, of the before mentioned application, and like numerals are applied to like parts herein.

Also, in Figs. 1 and 2, similar equivalent parts therein bear numerals similar to those found ip,

1933, Serial No. 666,551

Figs. 3 to 6, inclusive, but increased by one hundred. Y

The form of the invention shown in Figs. l and 2 is of unitary type. In said figures the numeral ||8 indicates the lowermost portion and mounted therein is a throttle valve |43 which controls the discharge to the outlet of conduit portion I 5 that discharges to a supply tank or reservoir. The inlet |48 may be characterized as of the low pressure type. It is adapted for connection to the discharge from a fluid operable motor device supplied by a source of pressure, such as a pump, the'intake of which naturally would be connected to the supply tank or reservoir for a circulatory system. l

superimposed upon the casing ||8 is a casing and the aforesaid constitutes the intermediate portion of the unit and includes the automatically operable valve for by-passing a portion of the fluid used for device operation control when the valve is automatically operated. This casing portion has the high pressure inlet |24 adapted for connection to the source of pressure. I'he head or upper portion of the casing includes a dome or chamber |35a. and mounted therein is a relief valve |09 which communicates with the inlet |24 as at |08 and which discharges to the chamber portion |26c in the head |35 as at |01. High pressure applied to the inlet |24 from a pump enters chamber |33 and upon excessive pressure is discharged through the relief yvalve |09 to the chamber portion |26c which communicates by the passage or intermediate chamber forming portion |261) in the casing |25 and which in turn communicates with the chamber forming portion |26a in the casing or lower portion ||8 thereof. Chamber portion I26a, as shown clearly in Fig. 2, is in free communication with the discharge H5,

In the intermediate casing portion is a bore |25a and in it is mounted a piston plunger valve having the piston head |38, the stem |a and the recessed valve portion |40, the exterior of which isV suitably provided with sealing rings. A spring |39 has one end nested in the piston valve recess and the other end, in the present form of the invention, bears upon the face |3911, of the head portion of the casing.

The casing |25 at one end and adjacent the high pressure intake, is provided with an arcuate chamber |33a. This chamber may be and preferably is cylindrical, if desired.' The chamber |33a is in direct communication with the chamber |33-see Fig. 1. A plurality of arcuately spaced radial ports |4| extend from the chamber -55 be provided. The arcuate or rather cylindrical' chamber |34a discharges bystheinterior exhaust passage |34-see Fig. 2-to the chamber portion |2513. In this form of the invention, port |42 may be omitted. This is because the coaxial opening in cover |39a permits relief of pressure behind the plunger valve to discharge 5zthrough |26c etc.

Thus, when the piston |38 has pressure ap- :pliedfto the lower face through'passage |31,the plunger valve is moved upwardly in opposition 'to .spring 'L39 and fthe'pressure fluid applied t0 ,inta-ke :1| 24 discharges fthroughthe ports Y .4 bore .|'25a and then discharges through `theports I4 a :to ntl'xeichaxnber |34a and thenceby means vof the discharge :or outlet portion :|34 ,to :the -chamber Within the-.ca-singfportion I |8 there isthe bore |f| 8a and frotatably, or ,razther pivotally, mounted therein;i s the manually operable Vvalve :|43 which carries astem vl-43a that extends through a retaining `seal construction, `indicated .by ,the numerals |50 yand 115|. A'coil spring I|44.norrnally opposes the valve so that it is in registrationwith the ports ,or passages -|.4.'8a andl41, the latter constituting an internal outlet or discharge to the chamber portion 1|26a.

The rotary .valve |-43 has a-relatively Wide arcuate andelongated opening |46 which communi- 4catesv with-a centralchamber |4Ea Vtherein and also communicating :with [said central chamber `is the narrower :elongated port or passage |45. The vvalve is shown in the vrpartially open .position in Fig. 2. Portions |45, and fISa ,constitute -alpassage through'valve |43.

V'It Will'beV recalled thatthe discharge fromthe fluid operable devicedischarges to the intake |48, :termed v'tfhelovv pressure intake, and the valve 'I4-3 .is Yadapted :to :restrict the flow of iluid thererthrough to vthe .passage outlet or discharge |41. When fthe valve'is rotated to partially lrestrict the passage of liiuid through the valve, then 'there .Will be created back pressure fin ythe intake |48.

A port |32` communicates With said intake and vby :means .of vthe passage z|21 discharges to a .passage .131. The positioning ofA the rotary valve, 'so .as to restrict :the `free flow of fluid from portions |48 to.|-41, createsla back pressure that 'is -applied v'to the loweriend of :the .piston v|38 .and serves fto velevate the ypiston iin opposition to the 'spring |39 `which piston valve, when elevated, 'bypasses high pressure `from the .intake |24 fto the .discharge |134. Thus part of -the pressure sup- `plied to the system is by-passed :to the discharge :||5. The amount of fpressureby-passed reduces itheamount `oi pressure Afluid supplied to the iiuid operable device 4and in this manner the fspeed of the fluid `operable device may be autofma'tically controlled without the Ybuilding up of -the excessive pressures i-n 'the entire system, which `system is of acharacterdisclosed in the vbefore mentioned application,

The 'valve stem supports anarm |3|J`and a portion |52 fis a flocking plunger backed `.by'ia spring |53 and the same is associated with a stop bracket |54 that may be integral with the casing portion ||8 or casing portion |25, as desired, but which is, as shown by the section lines, a separate piece. The plunger |52 serves to frictionally retain the rotary valve in its adjusted position.

It Will be observed also from Figs. 1 and 2 that the casing portionV I8 serves as the head of the cylindrical bore |25a in the intermediate casing portion |25 and that the head |35 has a portion l|39@ that serves as a head for said bore and as La spring retainer for the spring also included in said bore.

`-Injlligs 3 vto 6, inclusive, there is illustrated a modied'form of the invention which constituted the initial but which now is not the preferred form. 'This disclosure is substantially identical to that found in the co-pending application before referred to, and so far as possible identical .numerals `refer to identical or fsimilar parts.

In Figs. 3 and 4, there is illustrated the automatic valve. I-n saidvgures,33 indicates the high pressure intake,.33athe arcuate,1and, as fshown in Fig. 4, the cylindrical chamber YWhich'communi- .Cates :by,;radial Yports 4|a with the bore 25a in the casing 25. -The .discharge 34 communicates with an .f arCuate, and herein cylindrical, chamber 34a and Iradial ports .4 a falso in arcuately spaced relation connect said Achamber ito the lbore 25a. Mounted-in the-bore 25a is -the plungerpiston 38 Which'byrthestem 48 supports afvalve 40. Valve 40 is recessed as at. 3f8a and fis provided with the relief k'port or passage :42. A spring .39 is seated .inthe recessed portion 38af of `the piston valve and bears against one lend thereof, the opposite end.bearingagainstftheheadfor cover plate 35. The other Vend:of'..tlfie--cylinder'is closed-.by the end 36 having the passage .'31 therein.

When pressure'is yappliedA through the :passage .31

tothe piston 38, the valve Will be moved toward vthe 'spring .'39 in opposition'thereto and the high pressure supplied fto nthe intake 33 is exhausted through the outlet or discharge 134. When no pressure is applied ito 4the piston, .the spring"39 lmaintains 'the valve closed and no uid passes from the intake33-to the exhaust 34. f

In Figs.V 5 and 6, there is illustrated the manual valve which is identical With the throttle valve shown in the 4before imentioned application. The casing |`8 includes a bore-:I 8a, in which isrrotatably mounted the valve 43 having a chamber 45a, a relatively large arcuate port .46 and a relatively restricted arcuate port '45. These ports are elongated longitudinally 'as' shown in Fig. `5. The dis- .charge from ythe:iiuidoperabledevica disclosed in the before mentioned application, enters the passage 48 and is throttled by means of the rotary valve or has free communication lwith the portion 41 'or discharge, which, in turn, is adapted to discharge to a reservoir;

llhrottling of the discharge through `this valve .lcreatesa back `pressure in passage 48 and said back pressure is exerted through the port or passage v32 by-means ofaline21 that, while not shown rin these figures, is adapted to be connected at its other end, the opening 31. Thus, the reciprocatoryrpiston plunger valve .is adapted to vbe moved by the back pressure created in the discharge justed position 4by 'any suitable mechanism,such as shown in Figs. land 2.l

The `invention claimedi's:--

1. In'a valve arrangement, thecombination'of. a unitary 'casing structure with an external high pressure intake, a lower pressure external intake and an external discharge, said casing having-a'pair of bores therein, a reciprocating piston plunger valve in one bore, a manually operable rotary valve in other bore, said casing having a chamber in free communication with the discharge and an internal discharge to the rotary valve bore, and means'in the other bore for piston movement in one direction, said casing having another internal discharge from the reciprocating valve bore to the chamber, said piston valve being arranged to connect the-high pressure intake to the last mentioned internal discharge, said rotary valve when partially closed creating aback pressure upon the low pressure intake, said casing having a passage communicating with the latter intake and reciprocating valve bore to insure valve movement therein by the rotary valve created back pressure.

2. In a valve arrangement, the combination of a unitary casing structurewith an external high pressure intake, a lower pressure external intake and an external discharge, said casing having a pair of bores therein, a reciprocating 'piston plunger valve in one bore, a normally operable rotary valve in other bore, said casing having a chamber in free communication withl the discharge and an internal discharge-to the rotary valve bore, means in the other bore for piston movement in one direction, said casing havinganother internal discharge from the reciprocating valve bore to the chamber, said piston valve being arranged to connect the high pressure intake to the last mentioned internal discharge, said rotary valve when partially closed creating aback pressure upon the low pressure intake, said casingl having a passage communicating with-'theflatterintake and reciprocating valve bore to insure valve movement therein by the rotary valve created back pressure, and yielding means associated with the rotary valve for the purpose set forth.

3. In a valve arrangement, the" combination of a unitary casing structure with'an external high pressure intake, a lower pressure external intake and an external discharge, said casing having a pair of bores therein, 1a reciprocatingA piston plunger valve in one bore, a manually operable rotary valve in other bore, said casing having a chamber in free communication with the discharge and an internal discharge-to the rotary valve bore, means in the other bore for piston movement in one direction, said casing having another internal discharge from the reciprocating valve borerto the chambensaid piston valve 'being arranged to connect the high pressure intake to the last mentioned'internal discharge, said rotary valve when partiallyclosed creating a back pressure upon the low pressure intake, said casing having a passage communicating with the latter intake and reciprocating valve bore to insure'valve movement therein rby the rotary lvalve created back pressure, anda relief valve in free communication with the high pressure intake and enclosed with the chamber and'discharg'ing thereto for the purpose set forth.

4. In a valve arrangement, lth'e'cornbination of a unitary casing structure withlan external high pressure intake, a lower pressureexternal intake and an .external discharge',- said casing having a pair of bores therein, a reciprocating pistonplunger yvalve'in'one bore, a manually operable rotary valve in other bore, saidcasing having a chamber in free `com-munication with the discharge and an internal discharge to the rotary valve bore,means in the other bore for piston movement in one direction, said casing having another internal discharge from the reciprocating valve bore to the chamber, said piston valve being arranged to connect the high pressure intake to the last mentioned internal discharge-said rotary valvewhen partially closed creating a back'pressure upon the low pressure intake, said casing having a passage communicatingwith the latter intake and reciprocating valve bore to insure valve movement 'therein by the rotary valve created back pressure, anda relief valve inV free communication with the high pressure intake and discharging thereto for the purpose setforth.

5. In Va valve arrangement, the combination ofy a unitary casing structure with an external high pressure intake, a lower pressure external intake and an external discharge, said casing having a pair of bores therein, a reciprocating piston plunger valve in one bore, a manually operable rotary valve inother bore, said casing having a chamber in free communication with the discharge and an internal discharge to the rotary valve bore, means in theother bore for pistonmovement in one direction, said casing having anotherV internal discharge from the reciprocating valve bore to the chamber, said piston valve being arranged to connect the high pressure intake to the last mentioned internal discharge, said rotary valve when partially closed creating. a back pressure upon the low pressure intake, said casing having a passage communicating with the latter intake and reciprocating valve bore to insure valve movement therein by the rotary valve created back pressure, a relief valve in free communication with .the high pressureA intake'and enclosed' with the chamber and discharging thereto for the purposes set'forth, and yielding meansV associated with the rotary valve for the purpose set forth."` l

6.`In a valve arrangement, the combination of aunitary casing structure with an external high pressure intake, a lower pressure external intake and an external discharge, said casing having a pair of. bores therein, a reciprocating piston plunger valve in one bore, a manually operable rotary valve in the `other bore, said casing having a chamberin free communication with the discharge and an internal discharge to the rotaryV valve bore, means in the other bore for piston movement in one direction, said casing having another internal discharge from the reciprocating valve bore to the chamber, said piston valve being arranged to connect the high pressure intake to the last mentioned internal discharge, said rotary valve when partially closed creating a back pressure upon the low pressure intake, Said casing having a passage communicating with the latter intake and reciprocating valve'bore to insure valve movement therein by the rotaryvalve created back pressure, va relief valve in free communication with the high pressure intake and discharging thereto for the purpose set forth, and yielding means associated with the rotarywalve for the purpose set forth. v

v"7. A device as defined by claim 1, characterized bythe casing structure comprising three independent portions rigidly connected together, one portion including vthe. discharge, the low pressure intake and the rotaryV valveY bore, an-

other portion includingy the high pressure intake, the reciprocating. valve bore, and eachl of said portionsr including. a: portion of .the discharge chamber. f

8: A device as dened' by Aclaim 4, characterized". by` the casing'v structure comprising three independent portions rigidly connected together, one portion including the discharge, the low pressure intake and-,the rotary valvebore, another. portion including; the high pressure intake, the reciprocating valve bore, andA each of saidportions. andA the third portion including a portion of the discharge chamber, the third portion chamber-enclosing the relief. valve.

9. A device as defined by claim 4, characterized by the casingzstructure comprisingthree independent portions rigidly connected together, one portion. including the discharge, the low pressure intake and the rotary valve bore, another-*portion including. the high pressure intake, the reciprocating valve bore, and each .of said portions and the third portion including a. portionof the discharge chamber, the third portion chamber .enclosing therelief valve supported by the second portion; Y

10'. In a valve mechanismincluding an intake, an exhaust and a passage therebetween, the combination of a throttle valve in said passage and controlling the pressure o-f the iiuid passing throughthe mechanism, a second passage in'free communication with the intake and-continuously subjectrto back pressure created by the throttle valve, another intake, another exhaust and. a passageY therebetween, a valve member in said last mentioned passage operatively and continuously controlling theV communication therebetween, and'pressure operable meanscontrolling said valve member and connected to the first mentioned passage for continuous movement of the second 'mentioned valve in accordance. with the variation of the` back pressure.

11. A;va1veconstruction for continuouslyl and automatically regulating continuous ow, includingA a passage subject to a source of high pres- 1 sure, a valve arrangement therein, another; passure applied to the second rmentioned passage and create a back pressure ahead of the manually operable valve, and a. passage around the throttle valve to the first mentioned Valve arrangement, the Valve arrangement including a plunger piston valve, means normally constraining said piston valve to cut oif `communication in the rst mentioned passage, said' piston of the plungervalve being continuouslysubject to the pressure in the 'third mentioned passage and in proportion to the back pressure in the second mentioned passage and in'opposition to said constraining means for simultaneously and continuously regulating the flow through the rst and second mentionedpassages in response to back pressure variation. Y,

12. A- valve construction for continuously and automatically regulating continuous flow, includingV a passage subject to a source of high. pressure, a..valve arrangementtherein, anotherpassage subject to a lower pressureinitially derived from the. sourcev of high pressure, a second and manually operable valve in the second mentioned passage and adapted to throttle the lower. pressure ,appliedV to the second mentioned passage and create. a back pressure aheadof themanuallyoperablev valve, and.V a passage around the throttle valve to the first mentioned.'valve arrangement, the valve arrangement includingv a plunger pistonxvalvemeans normally constraining said piston va1ve.-toy cut olf communication in the firstA mentioned passage, said piston of the plunger valve being continuously subject to thepressure in thev third mentioned passage and in proportion tothe back pressure in the'second mentioned passage and in opposition to said con-` straining means for simultaneously and continuously regulating: thel flow throughthe rst and second mentioned: passages in response to back pressure variation, and a relief valve means for relieving excessive pressure in the rst mentioned passage. Y

13. A4 valvev construction for continuously and automatically regulating continuous flow, including' a passage subject to a rsource of high pressure, a valve arrangement. therein, another passage subject to alower pressure,v initially derived from the source ofA highpressure, a second and manually operable valve in the second mentioned passage and adapted to throttle the.d lower pressure Yapplied tofthe second mentioned passage and createa back` pressure ahead of the manually operable valve, and a passage around the throttle valve to the first. mentioned valve arrangementthe latter valve arrangement including a plunger. piston-Valve, meansnormally constraining said piston valve to cut off communication inthe first mentioned passage, said piston of the. plunger valve being Acontinuously vsubject to the pressure in the third mentioned passage and in proportiontothe back pressure in the second mentioned passage and in. opposition to said constraining means for simultaneouslyl and continuously regulating the flow throughthe first and second mentioned passages in response to back pressure variation, andv a relief valve means for relieving excessive pressure-of the first mentioned passage and operatively discharging to the discharge sideV of the manually operable valve.

14. In a valve. structure with a casing means having a cylindrical bore therein, an intake adjacent one end, anV arcuate chamber concentric with the bore and in free communication with the intake, an outlet adjacentA the other end of the casing-means, an varcuate chamber concentric with the bore andV in free communication with the outlet, each chamber having an arcuate port communicatingwith the bore, a hollo-W cylindrical valve inthe bore, anda piston plunger in the bore, the combination of a stem therefor in the bore and of less area. than the bore, said piston, stem and valve being of. less length than the. bore and. reciprocable therein, o-ne end of the bore having a port. therein to subject. the piston lto-pressurefor valvemovement, and spring means having` one endoperatively bearing at the opposite end of the. bore for opposing pressure movement and. having one .end nested in the hollow valve, said,A valve having a closed end adjacent the stem andapassage therein for pres.- sure relief to permitfree valve movement.

l5. vIn a.valve structure with-a lcasing means having a cylindrical bore therein, an intake adjacent` one end, an arcuate chamber concentric with the bore and in free communication with the intake, an outlet adjacent the other end of the casing means, anarcuat'e chamber concentric withV the bore and, in free4 communication with the outlet, each chamber having an arcuate por` communicatingwith the'bore, avalve in the bore, and apiston plunger in the bore, the combination of a stem therefor in the bore and of less area than the bore, said piston, stem and valve being of less length than the bore and reciprocable therein, one end of the bore having a port therein to subject the piston to pressure for valve movement, and spring means at the opposite end of the bore for opposing pressure movement, said valve having a passage therethrough for pressure relief to permit free valve movement.

16. In a valve structure with a casing means having a cylindrical bore therein, an intake adjacent one end, an arcuate chamber concentric with the bore and in free communication with the intake, an outlet adjacent the other end of the casing means, an arcuate chamber concentric with the bore and in free communication with the outlet, each chamber having an arcuate port communicating with the bore, a valve in the bore, and a piston plunger in the bore, the combination of a stem therefor in the bore and of less area than the bore, said piston, stem and valve being of less length than the bore and reciprocable therein, one end of the bore having a port therein to subject the piston to pressure for valve movement, and spring means at the opposite end of the bore for opposing pressure movement.

HURSHEL H. FITCH. 

